Which sections of the periodic table are excluded from the main group elements?

• A. Transition metals and inner transition metals
• B. Metalloids and nonmetals
• C. Halogens and noble gases
• D. Alkali metals and alkaline earth metals

Answer: (A)

Verified step by step guidance

1. Understand that the periodic table is divided into different blocks or sections based on the electron configurations of the elements.
2. Recognize that main group elements are typically found in the s-block and p-block of the periodic table, which include groups 1, 2, and 13 through 18.
3. Identify that transition metals are located in the d-block, which is between groups 3 and 12, and are not considered main group elements.
4. Note that inner transition metals are found in the f-block, which includes the lanthanides and actinides, and are also excluded from the main group elements.
5. Conclude that the sections excluded from the main group elements are the transition metals (d-block) and inner transition metals (f-block).